450 ISL or 600 ISX???

[conniep]

Thank you, that helps a lot.

[Baron37075]

Originally Posted by conniep

Thank you for your response. I am unaware of a weight penalty, please elaborate.

WEIGHT PENALTY
~1,800 lbs total for the ISX/Allison 4000 combo over the ISL/Allison 3000 combo. According to Cummins' literature, the ISX carries an additional 1,501 lbs over an ISL. It's my understanding the Allison 4000 transmission that's paired with the ISX weighs approximately 300 lbs more that the Allison 3000 that comes with the ISL.

Here's some more trivia...

STORAGE PENALTY
According to Tiffin Motorhome literature, the Allegro Bus with the ISX/Freightliner Chassis has ~165 cu. ft. of basement storage. The ISL/Powerglide Chassis has ~175 cu. ft. This could be due to the ISX/Freightliner's 10 inch shorter wheel base vs. the ISL/Powerglide and/or simply the ISX's larger engine size.

OIL PENALTY
Oil changes in either engine won't be cheap. But the ISX requires almost double the amount of oil vs. the ISL (14 gallons vs. 7.3 gallons).

HEIGHT DIFFERENCE
The ISX Allegro Bus is 4 inches taller than the ISL Allegro Bus. Not sure if this is a positive or negative. I guess it depends on how much clearance you need.

GAWR DIFFERENCE
The ISX/Freightliner has a higher front Gross Axle Weight Rating (GAWR), but lower GAWR for the rear and tag axles.

[conniep]

Thanks, that is very helpful.